In one or more implementations, the apparatus, systems and methods disclosed herein are directed to calibrating a smart phone with an arbitrary phone case for color lookup applications, wherein the calibration process includes obtaining, with the smartphone without the case equipped, a first measurement data set that includes at least one measurement of each of a black, white and grey calibration target; obtaining, with the smartphone with the case equipped, at least three exposure measurements of a white calibration target at least three different exposure times; calculating an optimized exposure time using at least the at least three exposure measurements; obtaining, with the smartphone with the case equipped, a second measurement data set that includes at least one measurement of each of a black, white and grey calibration target at the optimized exposure time; generating fitting parameters from the first and second measurement datasets; and storing the generated fitting parameters and optimized exposure time in at least one of a local or remote data storage device.

The Nondestructive Fluid Sensing System is a device that rapidly scans fluids to determine physical and chemical properties of the sample fluid. The Nondestructive Fluid Sensing System can detect the presence of a sample fluid with various optical and electrical sensors, and determines physical and chemical properties. The system features several innovations that increase sample throughput, reduces sample cross contamination, and eliminates waste products typically used in chemical tests. The system may be applied to various industries including manufacturing quality control, and healthcare.

A computer-implemented method for visualizing the appearances of at least two materials includes obtaining a first set of appearance attributes, the appearance attributes of the first set being associated with a first material, the first set of appearance attributes comprising measured appearance attributes, obtaining a second set of appearance attributes, the appearance attributes of the second set being associated with a second material; and obtaining a geometric model of at least one virtual object, the geometric model defining a three-dimensional macroscopic surface geometry of the virtual object. The invention is characterized by synthesizing a third set of appearance attributes from the first set of appearance attributes and the second set of appearance attributes and visualizing, using a display device, a scene comprising the at least one virtual object, using the third set of appearance attributes, a comparison set of appearance attributes and the geometric model, a first portion of the at least one virtual object being visualized using the third set of appearance attributes, and a second portion of the at least one virtual object being visualized using the comparison set of appearance attributes, to allow a direct a visual comparison of the first set of appearance attributes as modified by the second set of appearance attributes with the comparison set of appearance attributes.

A method of measuring the color of a surface may include a device positioned above the surface. The device may include an optical sensor and a display screen. The optical sensor measures visible light level reflected from the surface in a plurality of spectral channels. A plurality of patterns are sequentially displayed on the display screen. The optical sensor is used to measure light reflected by the surface during display of each pattern. A value is determined for the distance from the optical sensor to the illuminated region for a first local maximum of intensity of the measured light reflected by the surface. A location in a color space corresponding to a color of the surface or a reflectance spectrum of the surface is determined based on the visible light level in each spectral channel for the value of the distance corresponding to the first local maximum.

A method for illumination of an object to be observed to be observed and the background, the method comprising the steps of: obtaining a relationship between wavelength and spectral radiance of the object while the object and the background are illuminated by a first light source that emits light that has a continuous spectrum in the wavelength range from 380 nanometers and 780 nanometers, and determining a value of representative wavelength that corresponds to a maximum value of the spectral radiance of the object plotted against wavelength or values of representative wavelength that correspond to maximum values of the spectral radiance of the object plotted against wavelength; determining a value or values of comparative wavelength; and illuminating the object and the background with light of the value or values of representative wavelength and light of the value or values of comparative wavelength.

A device for determining the surface topology and associated color of a structure, such as a teeth segment, includes a scanner for providing depth data for points along a two-dimensional array substantially orthogonal to the depth direction, and an image acquisition means for providing color data for each of the points of the array, while the spatial disposition of the device with respect to the structure is maintained substantially unchanged. A processor combines the color data and depth data for each point in the array, thereby providing a three-dimensional color virtual model of the surface of the structure. A corresponding method for determining the surface topology and associate color of a structure is also provided.

A device such as a stylus may have a color sensor. The color sensor may have a color sensing light detector having a plurality of photodetectors each of which measures light for a different respective color channel. The color sensor may also have a light emitter. The light emitter may have an adjustable light spectrum. The light spectrum may be adjusted during color sensing measurements using information such as ambient light color measurements made with a color ambient light sensor that has a plurality of photodetectors each of which measures light for a different respective color channel. An inertial measurement unit may be used to measure the angular orientation between the stylus and an external object during color measurements. Arrangements in which the light emitter is modulated during color sensing may also be used. Measurements from the stylus may be transmitted wirelessly to external equipment.

The present invention relates to a color control system for controlling, in real time, the color of an article positioned on a moving carrier. The system comprises: an illuminating device configured to illuminate said moving article in successive illuminating cycles, each illuminating cycle comprising successively generating, at a given rate, a given number of lines of light having distinct spectral bands said lines of light being substantially perpendicular to the direction of movement; a detecting device configured to detect the light backscattered by the article successively illuminated by each of said lines of light, such as to generate for each dot of a given number of dots of an observation strip perpendicular to the direction of movement, a number of signals corresponding to the light backscattered by said dot; and a processing unit configured to determine at least one value representative of the color of said dot.

A sensor package includes a semiconductor sensor chip having multiple light sensitive regions each of which defines a respective light sensitive channel. An optical filter structure is disposed over the sensor chip and includes filters defining respective spectral functions for different ones of the light sensitive channels. In particular, the optical filter structure includes at least three optical filters defining spectral functions for tristimulus detection by a first subset of the light sensitive channels, and at least one additional optical filter defining a spectral function for spectral detection by a second subset of the light sensitive channels encompassing a wavelength range that differs from that of the first subset of light sensitive channels.

Optical property measurement using a sensor behind a display screen Examples of this application disclose a method for measuring optical properties of a target. The method comprises illuminating the target with an illumination area with a display screen in contact with the target, and analysing signals reflected from the target and transmitted back through the display screen to a sensor positioned behind the display screen, to determine the optical properties of the target.